The present disclosure relates to a temperature measurement method for measuring the temperature of an ultraviolet light transmittance member transmitting ultraviolet light, a temperature measurement device for an ultraviolet light transmittance member, and a light source device.
Use has increased for vacuum ultraviolet (VUV) light having a wavelength of 200 nm or less as: light sources of semiconductor exposure devices and liquid crystal exposure devices, and light sources of inspection apparatuses for masks used in these exposure devices and various substrates fabricated by these exposure devices. For example, a semiconductor exposure device utilizing an ArF excimer laser having an oscillation wavelength of 193 nm as a light source is already in practical use; and furthermore, research into a light source device that produces VUV light having the same 157 nm wavelength as an F2 laser and research into a light source device using a deuterium lamp having a high-intensity peak near the 160 nm wavelength is being earnestly pursued (e.g. see Japanese Unexamined Patent Application Publication No. 2005-275095A).
Calcium fluoride (CaF2: fluorite), magnesium fluoride (MgF2), crystal (SiO2), quartz (SiO2), and the like are known as materials that transmit ultraviolet light that has a wavelength in the region of 200 nm or less; and containers of lamps, windows, and other ultraviolet light transmittance members are manufactured using these materials (e.g. see Japanese Unexamined Patent Application Publication No. 2009-163965A, Japanese Unexamined Patent Application Publication No. 2009-532829A, and Japanese Unexamined Patent Application Publication No. 2012-79584A).